xref: /openbmc/qemu/hw/xen/xen_pt_graphics.c (revision 750541c4)
1 /*
2  * graphics passthrough
3  */
4 #include "qemu/osdep.h"
5 #include "qapi/error.h"
6 #include "xen_pt.h"
7 #include "xen-host-pci-device.h"
8 #include "hw/xen/xen-legacy-backend.h"
9 
10 static unsigned long igd_guest_opregion;
11 static unsigned long igd_host_opregion;
12 
13 #define XEN_PCI_INTEL_OPREGION_MASK 0xfff
14 
15 typedef struct VGARegion {
16     int type;           /* Memory or port I/O */
17     uint64_t guest_base_addr;
18     uint64_t machine_base_addr;
19     uint64_t size;    /* size of the region */
20     int rc;
21 } VGARegion;
22 
23 #define IORESOURCE_IO           0x00000100
24 #define IORESOURCE_MEM          0x00000200
25 
26 static struct VGARegion vga_args[] = {
27     {
28         .type = IORESOURCE_IO,
29         .guest_base_addr = 0x3B0,
30         .machine_base_addr = 0x3B0,
31         .size = 0xC,
32         .rc = -1,
33     },
34     {
35         .type = IORESOURCE_IO,
36         .guest_base_addr = 0x3C0,
37         .machine_base_addr = 0x3C0,
38         .size = 0x20,
39         .rc = -1,
40     },
41     {
42         .type = IORESOURCE_MEM,
43         .guest_base_addr = 0xa0000 >> XC_PAGE_SHIFT,
44         .machine_base_addr = 0xa0000 >> XC_PAGE_SHIFT,
45         .size = 0x20,
46         .rc = -1,
47     },
48 };
49 
50 /*
51  * register VGA resources for the domain with assigned gfx
52  */
53 int xen_pt_register_vga_regions(XenHostPCIDevice *dev)
54 {
55     int i = 0;
56 
57     if (!is_igd_vga_passthrough(dev)) {
58         return 0;
59     }
60 
61     for (i = 0 ; i < ARRAY_SIZE(vga_args); i++) {
62         if (vga_args[i].type == IORESOURCE_IO) {
63             vga_args[i].rc = xc_domain_ioport_mapping(xen_xc, xen_domid,
64                             vga_args[i].guest_base_addr,
65                             vga_args[i].machine_base_addr,
66                             vga_args[i].size, DPCI_ADD_MAPPING);
67         } else {
68             vga_args[i].rc = xc_domain_memory_mapping(xen_xc, xen_domid,
69                             vga_args[i].guest_base_addr,
70                             vga_args[i].machine_base_addr,
71                             vga_args[i].size, DPCI_ADD_MAPPING);
72         }
73 
74         if (vga_args[i].rc) {
75             XEN_PT_ERR(NULL, "VGA %s mapping failed! (rc: %i)\n",
76                     vga_args[i].type == IORESOURCE_IO ? "ioport" : "memory",
77                     vga_args[i].rc);
78             return vga_args[i].rc;
79         }
80     }
81 
82     return 0;
83 }
84 
85 /*
86  * unregister VGA resources for the domain with assigned gfx
87  */
88 int xen_pt_unregister_vga_regions(XenHostPCIDevice *dev)
89 {
90     int i = 0;
91     int ret = 0;
92 
93     if (!is_igd_vga_passthrough(dev)) {
94         return 0;
95     }
96 
97     for (i = 0 ; i < ARRAY_SIZE(vga_args); i++) {
98         if (vga_args[i].type == IORESOURCE_IO) {
99             vga_args[i].rc = xc_domain_ioport_mapping(xen_xc, xen_domid,
100                             vga_args[i].guest_base_addr,
101                             vga_args[i].machine_base_addr,
102                             vga_args[i].size, DPCI_REMOVE_MAPPING);
103         } else {
104             vga_args[i].rc = xc_domain_memory_mapping(xen_xc, xen_domid,
105                             vga_args[i].guest_base_addr,
106                             vga_args[i].machine_base_addr,
107                             vga_args[i].size, DPCI_REMOVE_MAPPING);
108         }
109 
110         if (vga_args[i].rc) {
111             XEN_PT_ERR(NULL, "VGA %s unmapping failed! (rc: %i)\n",
112                     vga_args[i].type == IORESOURCE_IO ? "ioport" : "memory",
113                     vga_args[i].rc);
114             return vga_args[i].rc;
115         }
116     }
117 
118     if (igd_guest_opregion) {
119         ret = xc_domain_memory_mapping(xen_xc, xen_domid,
120                 (unsigned long)(igd_guest_opregion >> XC_PAGE_SHIFT),
121                 (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
122                 3,
123                 DPCI_REMOVE_MAPPING);
124         if (ret) {
125             return ret;
126         }
127     }
128 
129     return 0;
130 }
131 
132 static void *get_vgabios(XenPCIPassthroughState *s, int *size,
133                        XenHostPCIDevice *dev)
134 {
135     return pci_assign_dev_load_option_rom(&s->dev, size,
136                                           dev->domain, dev->bus,
137                                           dev->dev, dev->func);
138 }
139 
140 /* Refer to Seabios. */
141 struct rom_header {
142     uint16_t signature;
143     uint8_t size;
144     uint8_t initVector[4];
145     uint8_t reserved[17];
146     uint16_t pcioffset;
147     uint16_t pnpoffset;
148 } __attribute__((packed));
149 
150 struct pci_data {
151     uint32_t signature;
152     uint16_t vendor;
153     uint16_t device;
154     uint16_t vitaldata;
155     uint16_t dlen;
156     uint8_t drevision;
157     uint8_t class_lo;
158     uint16_t class_hi;
159     uint16_t ilen;
160     uint16_t irevision;
161     uint8_t type;
162     uint8_t indicator;
163     uint16_t reserved;
164 } __attribute__((packed));
165 
166 void xen_pt_setup_vga(XenPCIPassthroughState *s, XenHostPCIDevice *dev,
167                      Error **errp)
168 {
169     unsigned char *bios = NULL;
170     struct rom_header *rom;
171     int bios_size;
172     char *c = NULL;
173     char checksum = 0;
174     uint32_t len = 0;
175     struct pci_data *pd = NULL;
176 
177     if (!is_igd_vga_passthrough(dev)) {
178         error_setg(errp, "Need to enable igd-passthrough");
179         return;
180     }
181 
182     bios = get_vgabios(s, &bios_size, dev);
183     if (!bios) {
184         error_setg(errp, "VGA: Can't get VBIOS");
185         return;
186     }
187 
188     if (bios_size < sizeof(struct rom_header)) {
189         error_setg(errp, "VGA: VBIOS image corrupt (too small)");
190         return;
191     }
192 
193     /* Currently we fixed this address as a primary. */
194     rom = (struct rom_header *)bios;
195 
196     if (rom->pcioffset + sizeof(struct pci_data) > bios_size) {
197         error_setg(errp, "VGA: VBIOS image corrupt (bad pcioffset field)");
198         return;
199     }
200 
201     pd = (void *)(bios + (unsigned char)rom->pcioffset);
202 
203     /* We may need to fixup Device Identification. */
204     if (pd->device != s->real_device.device_id) {
205         pd->device = s->real_device.device_id;
206 
207         len = rom->size * 512;
208         if (len > bios_size) {
209             error_setg(errp, "VGA: VBIOS image corrupt (bad size field)");
210             return;
211         }
212 
213         /* Then adjust the bios checksum */
214         for (c = (char *)bios; c < ((char *)bios + len); c++) {
215             checksum += *c;
216         }
217         if (checksum) {
218             bios[len - 1] -= checksum;
219             XEN_PT_LOG(&s->dev, "vga bios checksum is adjusted %x!\n",
220                        checksum);
221         }
222     }
223 
224     /* Currently we fixed this address as a primary for legacy BIOS. */
225     cpu_physical_memory_rw(0xc0000, bios, bios_size, 1);
226 }
227 
228 uint32_t igd_read_opregion(XenPCIPassthroughState *s)
229 {
230     uint32_t val = 0;
231 
232     if (!igd_guest_opregion) {
233         return val;
234     }
235 
236     val = igd_guest_opregion;
237 
238     XEN_PT_LOG(&s->dev, "Read opregion val=%x\n", val);
239     return val;
240 }
241 
242 #define XEN_PCI_INTEL_OPREGION_PAGES 0x3
243 #define XEN_PCI_INTEL_OPREGION_ENABLE_ACCESSED 0x1
244 void igd_write_opregion(XenPCIPassthroughState *s, uint32_t val)
245 {
246     int ret;
247 
248     if (igd_guest_opregion) {
249         XEN_PT_LOG(&s->dev, "opregion register already been set, ignoring %x\n",
250                    val);
251         return;
252     }
253 
254     /* We just work with LE. */
255     xen_host_pci_get_block(&s->real_device, XEN_PCI_INTEL_OPREGION,
256             (uint8_t *)&igd_host_opregion, 4);
257     igd_guest_opregion = (unsigned long)(val & ~XEN_PCI_INTEL_OPREGION_MASK)
258                             | (igd_host_opregion & XEN_PCI_INTEL_OPREGION_MASK);
259 
260     ret = xc_domain_iomem_permission(xen_xc, xen_domid,
261             (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
262             XEN_PCI_INTEL_OPREGION_PAGES,
263             XEN_PCI_INTEL_OPREGION_ENABLE_ACCESSED);
264 
265     if (ret) {
266         XEN_PT_ERR(&s->dev, "[%d]:Can't enable to access IGD host opregion:"
267                     " 0x%lx.\n", ret,
268                     (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT)),
269         igd_guest_opregion = 0;
270         return;
271     }
272 
273     ret = xc_domain_memory_mapping(xen_xc, xen_domid,
274             (unsigned long)(igd_guest_opregion >> XC_PAGE_SHIFT),
275             (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
276             XEN_PCI_INTEL_OPREGION_PAGES,
277             DPCI_ADD_MAPPING);
278 
279     if (ret) {
280         XEN_PT_ERR(&s->dev, "[%d]:Can't map IGD host opregion:0x%lx to"
281                     " guest opregion:0x%lx.\n", ret,
282                     (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
283                     (unsigned long)(igd_guest_opregion >> XC_PAGE_SHIFT));
284         igd_guest_opregion = 0;
285         return;
286     }
287 
288     XEN_PT_LOG(&s->dev, "Map OpRegion: 0x%lx -> 0x%lx\n",
289                     (unsigned long)(igd_host_opregion >> XC_PAGE_SHIFT),
290                     (unsigned long)(igd_guest_opregion >> XC_PAGE_SHIFT));
291 }
292